Ceramic Arc Discharge Vessel and Method of Manufacture

Abstract

A method of forming a hollow ceramic body ( 10 ) comprising the steps of: forming a first section half ( 12 ) with a given wall thickness T and a second section half ( 14 ) with the given wall thickness T, the first section half and the second section half containing a binder material; forming a first joining surface ( 16 ) on the first section and forming a second joining surface ( 18 ) on the second section, the first joining surface 16 and the second joining surface 18 having a wall thickness T 1 thinner than the given thickness; simultaneously heating the first and second joining surfaces ( 16, 18 ) to cause localized melting of the binder material; initially contacting the first joining surface with the second joining surface to form an interface region; and applying compression to the interface region to join the first section ( 12 ) to the second section ( 14 ) without the protrusion of any material into a discharge space ( 20 ) formed when the first section ( 12 ) and the second section ( 14 ) are joined.

1 . A method of forming a hollow ceramic body comprising the steps of:
 forming a first section half with a given wall thickness T and a second section half with said given wall thickness T, said first section half and said second section half containing a binder material;   forming a first joining surface on the first section and forming a second joining surface on the second section, said first joining surface and said second joining surface having a wall thickness T 1  thinner than said given thickness;   simultaneously heating said first and second joining surfaces to cause localized melting of the binder material;   initially contacting the first joining surface with the second joining surface to form an interface region; and   applying compression to the interface region to join the first section to the second section without the protrusion of any material into a discharge space formed when the first section and the second section are joined.   
   
   
       2 . The method of  claim 1  wherein the inside wall of said first section and the inside wall of said second section are tapered between T and T 1 . 
   
   
       3 . The method of  claim 2  wherein said the inside wall of said first section and the inside wall of said second section are tapered for a distance of 1 mm. 
   
   
       4 . A hollow, ceramic arc discharge vessel half comprising:
 a section with a given wall thickness deployed about a longitudinal axis and terminating in an edge; and   a joining surface formed at said edge, said joining surface being thinner than said given thickness.   
   
   
       5 . The hollow, ceramic arc tube half of  claim 4  wherein said thinner joining surface is formed by tapering the inside surface of said hollow arc discharge vessel half. 
   
   
       6 . A method of making a two-piece hollow ceramic body comprising the steps of:
 forming a first section half with a given wall thickness T formed about a centerline and a second section half with said given wall thickness T formed about said centerline, the ceramic body containing a binder material;   forming a first joining surface on said first section and forming a second joining surface on said second section, said first joining surface and said second joining surface having a wall thickness T 1  thinner than said given thickness; said thinner wall thickness T 1  being formed by an internal taper, the internal taper of the first section and the internal taper of the second section having an angle X between them;   simultaneously heating said first and second joining surfaces to cause localized melting of the binder material;   initially contacting the first joining surface with the second joining surface to form an interface region; and   applying compression to the interface region to join the first section to the second section without the protrusion of any material into a discharge space formed when the first section and the second section are joined.   
   
   
       7 . The method of making a two-piece hollow ceramic body according to  claim 1  wherein angle X is between 171 to 174 degrees, inclusive. 
   
   
       8 . An arc discharge vessel comprising a hollow ceramic body, the hollow ceramic body having a discharge space, the ceramic body having an internal, centrally located groove extending circumferentially around the discharge space. 
   
   
       9 . The arc discharge vessel of  claim 8  wherein the groove is v-shaped. 
   
   
       10 . The arc discharge vessel of  claim 8  wherein the groove is located at an interface where two sections of the hollow ceramic body have been joined. 
   
   
       11 . The arc discharge vessel of  claim 10  wherein the two sections are substantially identical.